1. Field of the Invention
The present invention relates to methods for manufacturing a conductive film typified by a wiring.
2. Description of the Related Art
In recent years, pattern formation using a droplet discharge method typified by an ink-jet method has been applied to a field of flat panel displays and actively developed. A droplet discharge method has many advantages in that no mask is required because patterns are directly drawn, application to a large-sized substrate is easy, and efficiency in the use of materials is high, for example. Therefore, a droplet discharge method has been applied to the manufacture of color filters, electrodes of plasma displays, or the like (for example, see Non-patent Document 1: T. Shimoda, Ink-jet Technology for Fabrication Processes of Flat Panel Displays, SID '03 DIGEST, pp. 1178-1181).
For example, a conductive film using a droplet discharge method is formed by coating of a composition containing conductive particles which are dispersed in a solvent, and then performing drying and baking thereof. Besides the solvent, an organic compound such as a dispersant which disperses conductive particles in a solvent is contained in the composition. Therefore, the organic compound is removed by decomposition and is baked at a high temperature to sinter the conductive particles.
In the meantime, a technology which uses ultraviolet irradiation at the same time as baking to suppress a baking temperature to be low is disclosed in Patent Document 1: Japanese Published Patent Application No. 2006-291347. Note that a value which depends on a substance used for a dispersant is disclosed as a wavelength of an ultraviolet ray to be used.
However, the temperature is as high as 150° C., and baking at a lower temperature is necessary in a case where a conductive film is formed over an organic film, a plastic substrate, or the like, for example.